53 lines
1.1 KiB
Markdown
53 lines
1.1 KiB
Markdown
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<div align="center">
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<img width="200" height="200"
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src="https://s3.amazonaws.com/pix.iemoji.com/images/emoji/apple/ios-11/256/crayon.png">
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<h1>@jimp/utils</h1>
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<p>Utils for jimp extensions.</p>
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</div>
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## Available Methods
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### isNodePattern
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Determines if function was passed an node callback.
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```js
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if (isNodePattern(cb)) {
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cb.call(this, null, this);
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}
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```
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### throwError
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Either throws the error or calls the callback with the error.
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```js
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if (/* check for error */) {
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return throwError.call(this, 'someError', cb);
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}
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```
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### scan
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Scans through a region of the bitmap, calling a function for each pixel.
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```js
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function removeRed(image) {
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return scan(image, 0, 0, image.bitmap.width, image.bitmap.height, function(
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x,
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y,
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index
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) {
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const red = this.bitmap.data[index + 0];
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const green = this.bitmap.data[index + 1];
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const blue = this.bitmap.data[index + 2];
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const alpha = this.bitmap.data[index + 3];
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this.bitmap.data[index + 0] = 0;
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this.bitmap.data[index + 1] = green;
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this.bitmap.data[index + 2] = blue;
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this.bitmap.data[index + 3] = alpha;
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});
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}
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```
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